Britain's Queen Elizabeth 11 officially welcomed America's first couple to Buckingham Palace Tuesday, with a Scots Guard band playing the U.S. national anthem.
President Barack Obama and first lady Michelle Obama watched a royal salute by the Guard of Honor before the president and Prince Philip, the duke of Edinburgh, reviewed the guard, walking up and down the ranks, the White House press pool reported.
A 41-gun salute was offered -- 21 because it was a royal event and 20 extra because it was in a royal park, a palace spokesman said.
Another 62 shots were fired at the Tower of London to mark the occasion.
Before noon (London time), the Obamas met with Prince Charles and Camilla, the duchess of Cornwall, at the U.S. ambassador's residence, where the Obamas spent the night after arriving from Ireland.
The four then traveled to Buckingham Palace for a luncheon hosted by the queen, Charles' mother.
The president was dressed in a dark suit with reddish tie. Michelle Obama wore a mint green silk dress with a pink bolero jacket.
Arriving at the palace, the presidential motorcade was greeted by the queen and Philip.
The queen's staff escorted the Obamas around the six-room suite they'll be occupying during their visit.
It is the same suite that Prince William and Catherine, duchess of Cambridge, used on their wedding night.